By any chance does Wales factor into your family tree? Olwyn, in old-world-Welsh, would have been pronounced: long O - l - long oo - un: "Olooun". Today's pronunciations have been influenced by ages of the surrounding Celtic tongues, and there are still distinct differences between north and south Wales. I imagine it's "Olwin" now. Right, Pat?

http://www.behindthename.com/name/ olwyn(remove the space)

Variant of Olwen:

"Means "white footprint" from Welsh ol "footprint, track" and gwen "white, fair, blessed". In Welsh legend Olwen was a beautiful maiden, the lover of Culhwch and the daughter of the giant Yspaddaden. Her father insisted that Culhwch complete several seemingly impossible tasks before he would allow them to marry, and Culhwch was successful with all of them.

Admittedly trivial info from someone who researched 31 years ago, before naming her firstborn, Branwyn.;-D